javascript count the number of occurrences in a string code example

Example 1: count occurrences of character in string javascript

var temp = "This is a string.";
var count = (temp.match(/is/g) || []).length;
console.log(count);

Output: 2

Explaination : The g in the regular expression (short for global) says to search the whole string rather than just find the first occurrence. This matches 'is' twice.

Example 2: how do i count the number of occurrences in a string javascript

function charCount(myChar, str) {
	let count = 0;

	for (let i = 0; i < str.length; i++) 
    if (str.charAt(i) == myChar) 
        count++
 return count;
}

Example 3: count value a to b character javascript

function count (string) {  
  var count = {};
  string.split('').forEach(function(s) {
     count[s] ? count[s]++ : count[s] = 1;
  });
  return count;
}

Example 4: count value a to b character javascript

const recorrences = ['a', 'b', 'c', 'a', 'b','a']
                .map(i => !!~i.indexOf('a'))
                .filter(i => i)
                .length;
console.log(`recorrences ${recorrences}`) 
//recorrences 3

Example 5: count value a to b character javascript

let counter = str => {
  return str.split('').reduce((total, letter) => {
    total[letter] ? total[letter]++ : total[letter] = 1;
    return total;
  }, {});
};

counter("aabsssd"); // => { a: 2, b: 1, s: 3, d: 1 }

Example 6: Count Total Amount Of Specific Word In a String JavaScript

Here are two methods (Scroll down please here!) to find the total number of occurrence match
words in the string.

The first function allows you to give a query as input.
The second one uses the .match function of JavaScript.

Both introduced methods are resistant for any chars and 
independent of splitter and separator like " " or ",".

str1 is your query

str1 = "fake";  

str2 is the whole string:

var inputString = "fakefakefakegg fake 00f0 221 Hello wo fake misinfo
fakeddfakefake , wo  431,,asd misinfo misinfo co wo fake sosis bandari
mikhori?, fake fake fake ";

Method 1 : use .indexOf or .search function of JavaScript 
(advantage you can give input)


function CountTotalAmountOfSpecificWordInaString(str1, str2)
{
    let next = 0;
    let findedword = 0;
        do {
            var n = str2.indexOf(str1, next);
            findedword = findedword +1;
            next = n + str1.length;
            }while (n>=0);
     console.log("total finded word :" , findedword - 1 );
     return findedword;
   }
Method 2 : use .match function of JavaScript:



/**
 * @return {number}
 *  you have to put fake as query manually in this solution!!! disadvantage
 */

function CountTotalAmountOfMachedWordInaString(str2) {
    let machedWord = 0;
    machedWord = str2.match(/fake/g).length; 
    console.log("total finded mached :" , machedWord);
    return machedWord;
}
call the functions (Inputs):

CountTotalAmountOfSpecificWordInaString("fake" , "fake fakefakegg fake 00f0 221 Hello wo fake rld fakefakefake , wo lklsak dalkkfakelasd co wo fake , fake fake fake" );
CountTotalAmountOfMachedWordInaString("sosis bandarie fake  khiyarshour sosis , droud bar fake to sosis3");